[Supras] Portable F/A ratio meter?

[Jim Wooden]

Just for grins I'd like to check the F/A ratio of my supra under 
various operating conditions and with/without the coolant temperature 
sender modification.
Since this would not be a "permanent" installation I'd be happy to 
put the sensor in the tailpipe and run the wires back thru the hatch 
to the meter so that I could watch it while driving.

Any suggestions on how to make this happen without spending a 
boatload of cash are much apprecaited!

Thanks,
Jim Wooden
original owner 86.5 MkIII NA